//  //  //
//  Asia London NY Sessions based bg color
//  //  //

asia = time( timeframe.period, "1800-0300")
ls = time( timeframe.period, "0300-1200")
ns = time( timeframe.period, "0800-1800")
Asia = na(asia) ? na : color.blue
London = na(ls) ? na : color.green
NY = na(ns) ? na : color.red

bgcolor(Asia, title="Asia")
bgcolor(London, title="London")
bgcolor(NY, title="New York")